Research Soil Water Movement And Salt Transport Of Drip Irrigation Under Film On The Field

Drip irrigation under mulch has applied for exploitation of salinized land and secondary alkalization prevention and treatment. But there are also many problems in agricultural production guiding like making salt leaching model and irrigation system.The experiment data is gotten from the key irrigation station in Bbayingolin Mongol autonomous. Experiment includes bare land point infiltration experiments and drip irrigation test under mulch film in plastic. Referring to abroad and home research results, this paper has research in water content distribution and characteristics of soil water and salt movement, under drip irrigation under mulch. The following results can be concluded:(1)In bare land point infiltration experiment, soil saturated pond change law is similar with horizontal wetted radius. The results indicate that power function fits well to the advances of horizontal wet front and ponding water area with time .the deviation of forecast value is obvious when the initial period data is used to predict the wetting front.(2)In drip irrigation under mulch experiment, the soil water content is low around dripper and developed around gradually before drip irrigation, but it is increase after irrigation, soil salt became light obviously and decreases around gradually. This result is similar with bare land point infiltration experiment. In cotton development stages, water content is obvious different before and after each treatment. With time process, the water content in different soil layers all in decreasing.(3)There was positive correlation between water content and irrigation quota within 60cm depth. It must be consideration to irrigation quota and irrigating system under the condition of definite water supply, in order to keep higher water content. High irrigation frequency and small irrigation quota has prominent effect on soil salt leaching. With the irrigation period prolonged, mulch is more important for helping the soil maintain high water content and low salt. So the mulch is very important for the areas can't ensure irrigation frequently.(4)Irrigation quota is the most important factor by comparative analysis of soil salt content in main root zone and cotton yield, it has the most significant influence on output. the next is irrigation frequency. The most suited establishment irrigating system pattern for local conditions in 2007is irrigation frequency is 7days, irrigation quota is 260m3/mu.